Carmy -- I'll take a stab at the few questions I know I can answer.
Only submit one project at a time, wait for your response on that one and then decide what to do with the second ms.
Yes, it is professional and appropriate to mention previous representation as well as the houses that the ms you're submitting has been shopped to.
You probably shouldn't query until your 30-days are up unless you're upfront in the query regarding said 30-days. i.e. "My thirty day opt-out ends 10/31/06."